From dot at dotat.at  Tue Jan  1 18:16:49 2008
From: dot at dotat.at (Tony Finch)
Date: Tue, 1 Jan 2008 23:16:49 +0000
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
Message-ID: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>

http://kitenet.net/~joey/blog/entry/leap_second_mystery/

Tony.
-- 
f.a.n.finch  <dot at dotat.at>  http://dotat.at/
FISHER GERMAN BIGHT HUMBER: EAST OR SOUTHEAST 5 OR 6, OCCASIONALLY 7, PERHAPS
GALE 8 LATER IN FISHER. MODERATE OR ROUGH. SHOWERS, SOME WINTRY. MODERATE OR
GOOD.

From sla at ucolick.org  Tue Jan  1 18:47:04 2008
From: sla at ucolick.org (Steve Allen)
Date: Tue, 1 Jan 2008 15:47:04 -0800
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
Message-ID: <20080101234704.GA22030@ucolick.org>

On Tue 2008-01-01T23:16:49 +0000, Tony Finch hath writ:
> http://kitenet.net/~joey/blog/entry/leap_second_mystery/

Yep, again.

Paraphrasing the intro in each edition of Bulletin C

To authorities responsible for the measurement and distribution of
time:

Bulletin C is *not* a workable system, it's a 19th century scheme,
and the NTP servers of the world are hurting as a result.

Whether or not you want to keep leap seconds, please update this
scheme so that it conforms to 21st century notions of operational
with better availability than the hpiers.obspm.fr webserver and
verifiable and non-repudiable authoritative content.

--
Steve Allen                 <sla at ucolick.org>                WGS-84 (GPS)
UCO/Lick Observatory        Natural Sciences II, Room 165    Lat  +36.99855
University of California    Voice: +1 831 459 3046           Lng -122.06015
Santa Cruz, CA 95064        http://www.ucolick.org/~sla/     Hgt +250 m

From sanjeev at esysmail.com  Tue Jan  1 18:59:21 2008
From: sanjeev at esysmail.com (Sanjeev K Gupta)
Date: Wed, 2 Jan 2008 07:59:21 +0800
Subject: [LEAPSECS] Out of Office till 07 Jan 2008
Message-ID: <OF118FB259.FA911F79-ON482573C3.0083C6F9-482573C3.0083C6F9@esysmail.com>




I am available at +852 6124 5565


From imp at bsdimp.com  Tue Jan  1 20:15:31 2008
From: imp at bsdimp.com (M. Warner Losh)
Date: Tue, 01 Jan 2008 18:15:31 -0700 (MST)
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080101234704.GA22030@ucolick.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
Message-ID: <20080101.181531.-155800321.imp@bsdimp.com>

In message: <20080101234704.GA22030 at ucolick.org>
            Steve Allen <sla at ucolick.org> writes:
: On Tue 2008-01-01T23:16:49 +0000, Tony Finch hath writ:
: > http://kitenet.net/~joey/blog/entry/leap_second_mystery/
: 
: Yep, again.
: 
: Paraphrasing the intro in each edition of Bulletin C
: 
: To authorities responsible for the measurement and distribution of
: time:
: 
: Bulletin C is *not* a workable system, it's a 19th century scheme,
: and the NTP servers of the world are hurting as a result.
: 
: Whether or not you want to keep leap seconds, please update this
: scheme so that it conforms to 21st century notions of operational
: with better availability than the hpiers.obspm.fr webserver and
: verifiable and non-repudiable authoritative content.

AMEN BROTHER!

I think leap seconds are evil, and must die, but I think this
antiquated way of distributing leap seconds may be the root of most
evilness in the current scheme.

Warner

From magnus at rubidium.dyndns.org  Tue Jan  1 20:35:19 2008
From: magnus at rubidium.dyndns.org (Magnus Danielson)
Date: Wed, 02 Jan 2008 02:35:19 +0100 (CET)
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080101.181531.-155800321.imp@bsdimp.com>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<20080101.181531.-155800321.imp@bsdimp.com>
Message-ID: <20080102.023519.2101044986.cfmd@bredband.net>

From: "M. Warner Losh" <imp at bsdimp.com>
Subject: Re: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
Date: Tue, 01 Jan 2008 18:15:31 -0700 (MST)
Message-ID: <20080101.181531.-155800321.imp at bsdimp.com>

> In message: <20080101234704.GA22030 at ucolick.org>
>             Steve Allen <sla at ucolick.org> writes:
> : On Tue 2008-01-01T23:16:49 +0000, Tony Finch hath writ:
> : > http://kitenet.net/~joey/blog/entry/leap_second_mystery/
> : 
> : Yep, again.
> : 
> : Paraphrasing the intro in each edition of Bulletin C
> : 
> : To authorities responsible for the measurement and distribution of
> : time:
> : 
> : Bulletin C is *not* a workable system, it's a 19th century scheme,
> : and the NTP servers of the world are hurting as a result.
> : 
> : Whether or not you want to keep leap seconds, please update this
> : scheme so that it conforms to 21st century notions of operational
> : with better availability than the hpiers.obspm.fr webserver and
> : verifiable and non-repudiable authoritative content.
> 
> AMEN BROTHER!
> 
> I think leap seconds are evil, and must die, but I think this
> antiquated way of distributing leap seconds may be the root of most
> evilness in the current scheme.

For use on the Internet (important scooping, there are many non-internet based
systems out there, some for a very good reason) a very simple means of
achieving is by using DNS. Considering the type of information, which rarely
change, it fits the type of data DNS is able to announce. If using the
security features which is there for DNS, the DNS entry will be possible to
authenticate using already existing software methods. I know of at least one
TLD (.se) that can provide that service (as the authentication chain has its
root at the TLD).

The changes needed in NTP software or indeed any other software should not be
too hard to acomplish. The biggest thing could be to include the DNS
authentication enabled code, which should be out there anyway.

A little care should be paid to ensure that not only the upcomming leap second
is annouced as well as the UTC-TAI difference, but also when previous
leap seconds occured such that the full list is available, i.e. that all the
leap second decissions is announced.

For use over Internet, this is a modern approach.

I think I know who I would call, to provide the service in a robust fashion.

Another approach would be to use a webserver, but it would need the
authenticated DNS entry anyways to acheive the full service.

Cheers,
Magnus

From cowan at ccil.org  Tue Jan  1 21:32:44 2008
From: cowan at ccil.org (John Cowan)
Date: Tue, 1 Jan 2008 21:32:44 -0500
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080101234704.GA22030@ucolick.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
Message-ID: <20080102023244.GH14528@mercury.ccil.org>

Steve Allen scripsit:

> Bulletin C is *not* a workable system, it's a 19th century scheme,
> and the NTP servers of the world are hurting as a result.

Following the links suggests that the problem had to do with tier-0 clocks.
It looks like NTP should be modified to apply a Byzantine-generals algorithm
at each potential leap second to decide whether one is really happening or not.

> Whether or not you want to keep leap seconds, please update this
> scheme so that it conforms to 21st century notions of operational
> with better availability than the hpiers.obspm.fr webserver and
> verifiable and non-repudiable authoritative content.

Verifiable, fine.  But non-repudiable?  Do you actually suppose that
IERS will schedule a leap second and then announce that they never did
anything of the kind, such that it will be necessary to prove otherwise?
I doubt it.

-- 
Even a refrigerator can conform to the XML      John Cowan
Infoset, as long as it has a door sticker       cowan at ccil.org
saying "No information items inside".           http://www.ccil.org/~cowan
        --Eve Maler

From ashley at semantic.org  Tue Jan  1 21:37:27 2008
From: ashley at semantic.org (Ashley Yakeley)
Date: Tue, 01 Jan 2008 18:37:27 -0800
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080101234704.GA22030@ucolick.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
Message-ID: <1199241447.7297.2.camel@glastonbury>

On Tue, 2008-01-01 at 15:47 -0800, Steve Allen wrote:
> Whether or not you want to keep leap seconds, please update this
> scheme so that it conforms to 21st century notions of operational
> with better availability than the hpiers.obspm.fr webserver and
> verifiable and non-repudiable authoritative content.

We need something like this for TZ too.

-- 
Ashley Yakeley



From seaman at noao.edu  Tue Jan  1 21:48:02 2008
From: seaman at noao.edu (Rob Seaman)
Date: Tue, 1 Jan 2008 19:48:02 -0700
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080102.023519.2101044986.cfmd@bredband.net>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<20080101.181531.-155800321.imp@bsdimp.com>
	<20080102.023519.2101044986.cfmd@bredband.net>
Message-ID: <CF2C7091-E8B9-4555-B0F2-AA7534B8C758@noao.edu>

M. Warner Losh said:

> I think leap seconds are evil, and must die, but I think this
> antiquated way of distributing leap seconds may be the root of most  
> evilness in the current scheme.

The entire ridiculous discussion (and the unilateral attempt to  
steamroller a "solution") does come down to whether leap seconds are  
regarded as a necessary evil.

It would be refreshing to design a time distribution system from the  
top down, starting with an unbiased requirements discovery phase.  I  
don't give a damn for leap seconds, after all - rather, I'm a staunch  
supporter of maintaining civil mean solar time as distinct from  
interval time.

Magnus Danielson wrote:

> For use on the Internet (important scooping, there are many non- 
> internet based systems out there, some for a very good reason) a  
> very simple means of achieving is by using DNS.

See the NTP working group:

	https://lists.ntp.org/mailman/listinfo/ntpwg

for a discussion on this topic almost LEAPSECS-like in its bloated  
density.

Rob Seaman
National Optical Astronomy Observatory


From sla at ucolick.org  Tue Jan  1 21:55:17 2008
From: sla at ucolick.org (Steve Allen)
Date: Tue, 1 Jan 2008 18:55:17 -0800
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <1199241447.7297.2.camel@glastonbury>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
Message-ID: <20080102025517.GA22736@ucolick.org>

On Tue 2008-01-01T18:37:27 -0800, Ashley Yakeley hath writ:
> We need something like this for TZ too.

In the case of TZ, there is no single authority other than, as is
being posited in the Internet discussions of unique nomenclature for
zones, IANA.

And in cases like that of Hugo Chavez with Venezuela last year,
even the authority can be sorely confused.
Which is why non-repudiable *is* a good idea.

What would IANA have done in the case of Venezuela?
Issue an update and then a week later issue another update?

--
Steve Allen                 <sla at ucolick.org>                WGS-84 (GPS)
UCO/Lick Observatory        Natural Sciences II, Room 165    Lat  +36.99855
University of California    Voice: +1 831 459 3046           Lng -122.06015
Santa Cruz, CA 95064        http://www.ucolick.org/~sla/     Hgt +250 m

From cowan at ccil.org  Tue Jan  1 22:04:06 2008
From: cowan at ccil.org (John Cowan)
Date: Tue, 1 Jan 2008 22:04:06 -0500
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080102025517.GA22736@ucolick.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
Message-ID: <20080102030406.GJ14528@mercury.ccil.org>

Steve Allen scripsit:

> In the case of TZ, there is no single authority other than, as is
> being posited in the Internet discussions of unique nomenclature for
> zones, IANA.

IANA is not an authority (google for "names are but names"), it's a
gatekeeper for a bulletin-board that prevents anyone from posting on it
who hasn't gone through a defined process.

> And in cases like that of Hugo Chavez with Venezuela last year, even
> the authority can be sorely confused.  Which is why non-repudiable *is*
> a good idea.

If the Government of Venezuela or any other country changes its mind
about what the time zone in that country is, no one else in the world
has a thing to say about it.  There is and can be no contract, and so
non-repudiation remains irrelevant.

> What would IANA have done in the case of Venezuela?
> Issue an update and then a week later issue another update?

Of course.  The Olsen TZ database is updated about 10 times a year because
of such governmental whims.

Civil time is the creation of civil authority, and has exactly as much
relationship to mean solar time (or universal time, for that matter)
as the civil authority thinks convenient.

-- 
You're a brave man! Go and break through the            John Cowan
lines, and remember while you're out there              cowan at ccil.org
risking life and limb through shot and shell,           http://ccil.org/~cowan
we'll be in here thinking what a sucker you are!
        --Rufus T. Firefly

From ashley at semantic.org  Tue Jan  1 22:07:30 2008
From: ashley at semantic.org (Ashley Yakeley)
Date: Tue, 1 Jan 2008 19:07:30 -0800
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080102025517.GA22736@ucolick.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
Message-ID: <98E69265-633B-48BC-B1D9-318A71336E31@semantic.org>

On Jan 1, 2008, at 18:55, Steve Allen wrote:

> And in cases like that of Hugo Chavez with Venezuela last year,
> even the authority can be sorely confused.
> Which is why non-repudiable *is* a good idea.
>
> What would IANA have done in the case of Venezuela?
> Issue an update and then a week later issue another update?

I don't think non-repudiability is relevant for TZ at least.  
Venezuela is free to announce and revise time zone changes as often  
as it likes.

-- 
Ashley Yakeley



From magnus at rubidium.dyndns.org  Tue Jan  1 22:13:09 2008
From: magnus at rubidium.dyndns.org (Magnus Danielson)
Date: Wed, 02 Jan 2008 04:13:09 +0100 (CET)
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080102030406.GJ14528@mercury.ccil.org>
References: <1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<20080102030406.GJ14528@mercury.ccil.org>
Message-ID: <20080102.041309.-1233407311.cfmd@bredband.net>

From: John Cowan <cowan at ccil.org>
Subject: Re: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
Date: Tue, 1 Jan 2008 22:04:06 -0500
Message-ID: <20080102030406.GJ14528 at mercury.ccil.org>

> > And in cases like that of Hugo Chavez with Venezuela last year, even
> > the authority can be sorely confused.  Which is why non-repudiable *is*
> > a good idea.
> 
> If the Government of Venezuela or any other country changes its mind
> about what the time zone in that country is, no one else in the world
> has a thing to say about it.  There is and can be no contract, and so
> non-repudiation remains irrelevant.
> 
> > What would IANA have done in the case of Venezuela?
> > Issue an update and then a week later issue another update?
> 
> Of course.  The Olsen TZ database is updated about 10 times a year because
> of such governmental whims.
> 
> Civil time is the creation of civil authority, and has exactly as much
> relationship to mean solar time (or universal time, for that matter)
> as the civil authority thinks convenient.

In the same fashion, we must recognice that it is the civil authority that
decides weither the civil time is being UTC or UT1 based. We must also recall
that it remains for the civil authorities to decide weither they want leap
seconds or not.

Where a civil authority has chosen UT1 (using terms such as GMT or mean solar
time or whatever) UTC will not act as a ticker for civil time. This used to be
of a minor detail, but I am not sure it can be argued as a minor detail
anymore.

It seems like some countries is considering moving from UTC to TAI plus some
fixed offset.

Cheers,
Magnus

From greg.hennessy at cox.net  Tue Jan  1 22:35:00 2008
From: greg.hennessy at cox.net (Greg Hennessy)
Date: Tue, 01 Jan 2008 22:35:00 -0500
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080101234704.GA22030@ucolick.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
Message-ID: <477B0664.9050505@cox.net>

> Bulletin C is *not* a workable system, it's a 19th century scheme,
> and the NTP servers of the world are hurting as a result.

Bulletin C is mailed to lots of people around the world. It is also 
available on a web site. In what way is publishing a peice of paper not 
workable? What would you rather have?

I note that Bulletin C is 1800 characters, 184 words,
and 47 lines to note that nothing is supposed to happen
this past Dec 31st. :)




From seaman at noao.edu  Tue Jan  1 23:06:12 2008
From: seaman at noao.edu (Rob Seaman)
Date: Tue, 1 Jan 2008 21:06:12 -0700
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080102030406.GJ14528@mercury.ccil.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<20080102030406.GJ14528@mercury.ccil.org>
Message-ID: <3F4CF245-C067-43A3-A1C8-3B1308FC4646@noao.edu>

John Cowan wrote:

> If the Government of Venezuela or any other country changes its mind
> about what the time zone in that country is, no one else in the world
> has a thing to say about it.  There is and can be no contract, and so
> non-repudiation remains irrelevant.

International treaties have the force of law in the U.S., I believe,  
and presumably in other countries as well.  What is NAFTA, but a  
contract between nations?  So the assertion is that countries from  
Sudan to Bhutan can move their timezones around with gleeful abandon,  
but are somehow restricted by the ITU from issuing their own leap  
seconds?  Otherwise, what then is the point of the ITU?

> Civil time is the creation of civil authority, and has exactly as much
> relationship to mean solar time (or universal time, for that matter)
> as the civil authority thinks convenient.


The entire stoopid argument for ditching mean solar time centers on  
seeking lock step synchronization - strangely, precisely because we're  
deemed too craven to keep our clocks set properly.  Here you argue the  
opposite - that no possible ties can (or should?) bind our august  
authorities.

"Civil time" is also a term used in multiple ways in this discussion.   
Your meaning here is that each country (or even municipality?) can  
have a distinct system of time.  Clearly something underlies these  
diverse local conventions.  This common international standard,  
accessible to all, is what has been the focus of much of our  
discussions.

Rob


From dot at dotat.at  Wed Jan  2 13:17:03 2008
From: dot at dotat.at (Tony Finch)
Date: Wed, 2 Jan 2008 18:17:03 +0000
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080102025517.GA22736@ucolick.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
Message-ID: <Pine.LNX.4.64.0801021802260.25482@hermes-1.csi.cam.ac.uk>

On Tue, 1 Jan 2008, Steve Allen wrote:
>
> In the case of TZ, there is no single authority other than, as is
> being posited in the Internet discussions of unique nomenclature for
> zones, IANA.

IANA does not keep any timezone registry, and Internet protocols have for
a long time avoided using time zone names (relying instead on explicit
offsets).

Perhaps you are thinking of the Unicode Common Locale Data Repository
project <http://www.unicode.org/cldr/>. They use the Olson TZ names as the
basis of their standard, though augmented with a canonicalization table
for better long-term stability, and with "display names" to conform to
local standards instead of programming convenience.

> What would IANA have done in the case of Venezuela?
> Issue an update and then a week later issue another update?

The CLDR also defers to the Olson TZ database for details of the
definitions of zones, and includes a version number in case separate
systems need to be sure they agree about the timezone rules. In the case
of Venezuela the changes came fast enough to cause only one new tzdata
release.

Tony.
-- 
f.a.n.finch  <dot at dotat.at>  http://dotat.at/
HUMBER: SOUTHEAST 6 OR 7, PERHAPS GALE 8 LATER. ROUGH OR VERY ROUGH. WINTRY
SHOWERS, RAIN LATER. GOOD BECOMING MODERATE.

From cowan at ccil.org  Wed Jan  2 13:28:58 2008
From: cowan at ccil.org (John Cowan)
Date: Wed, 2 Jan 2008 13:28:58 -0500
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <Pine.LNX.4.64.0801021802260.25482@hermes-1.csi.cam.ac.uk>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<Pine.LNX.4.64.0801021802260.25482@hermes-1.csi.cam.ac.uk>
Message-ID: <20080102182858.GN14528@mercury.ccil.org>

Tony Finch scripsit:

> Internet protocols have for a long time avoided using time zone names
> (relying instead on explicit offsets).

That works for most Internet protocols because they deal with the past
and the present but not the future.  RFC 2445 (iCal) is an exception,
and suggests but does not require the use of Olson timezone names.
It also provides (in 4.2.19) that time zone names beginning with a slash
are defined by a globally unique TZ name registry (not yet created).

-- 
Kill Gorgun!  Kill orc-folk!            John Cowan
No other words please Wild Men.         cowan at ccil.org
Drive away bad air and darkness         http://www.ccil.org/~cowan
with bright iron!   --Ghan-buri-Ghan    http://www.ccil.org/~cowan

From cowan at ccil.org  Wed Jan  2 13:58:51 2008
From: cowan at ccil.org (John Cowan)
Date: Wed, 2 Jan 2008 13:58:51 -0500
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <3F4CF245-C067-43A3-A1C8-3B1308FC4646@noao.edu>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<20080102030406.GJ14528@mercury.ccil.org>
	<3F4CF245-C067-43A3-A1C8-3B1308FC4646@noao.edu>
Message-ID: <20080102185850.GO14528@mercury.ccil.org>

Rob Seaman scripsit:

> International treaties have the force of law in the U.S., I believe,  
> and presumably in other countries as well.  What is NAFTA, but a  
> contract between nations?

True but irrelevant, since (with one exception) local civil time is not
the subject of any international treaties that I know of.

The EU insists that its members all change from standard to summer time
at the same UTC second (unlike the story in North America where the
change happens in a rolling fashion from east to west), but carefully
abstains from prescribing which countries belong to which time zones,
in accordance with the principle of subsidiarity.

> So the assertion is that countries from
> Sudan to Bhutan can move their timezones around with gleeful abandon,  

Indeed.  Local civil time is and always has been a matter of national
sovereignty, possibly delegated to more local authorities.  In the U.S.,
states can petition to change standard time zones as a whole or in part,
but the changes are not always granted: DST is, I believe, still entirely
a state option.

> but are somehow restricted by the ITU from issuing their own leap  
> seconds?

They could, of course, do so, at the expense of being out of step with
the rest of the world.  It is choice, not compulsion, that makes every
nation synchronize its LCT with UTC either de jure or de facto.

> Otherwise, what then is the point of the ITU?

The same as the point of ISO and other purveyors of standards, essentially
none of which are internationally mandatory.

> The entire stoopid argument for ditching mean solar time centers on  
> seeking lock step synchronization - strangely, precisely because we're  
> deemed too craven to keep our clocks set properly.

Not as far as I know.  Apart from the ALHP proponents, the desire of
people who want to see an end to leap seconds is to redefine the day
as precisely 86400 SI seconds, and when the discrepancy between MSolT
(which is not quite LSolT, be it noted) and LCT becomes annoyingly large
in a particular place, to adjust the local UTC-TI offset accordingly,
just as we will eventually have to adjust the Gregorian calendar when
the discrepancy between the tropical year and the civil year becomes
annoyingly large (something that will probably not happen in all countries
at the same time, any more than the adoption of the Gregorian calendar
happened uniformly in 1583).

> Here you argue the opposite - that no possible ties can (or
> should?) bind our august authorities.

I don't argue anything: I state the facts of international law.
Countries could bind themselves by treaty to observe a uniform LCT
system, but they have not.  Whether they should or should not is
a question I feel no compulsion to answer.

> "Civil time" is also a term used in multiple ways in this discussion.   

Not by me, certainly.  I use the term "local civil time" or "LCT"
solely to mean whatever time a clock that is correctly set by local
law registers at a particular place, and the timescale derived from the
sequence of those settings.

> Your meaning here is that each country (or even municipality?) can  
> have a distinct system of time.  Clearly something underlies these  
> diverse local conventions.  

Indeed, but there is neither legal nor metaphysical necessity for
it to be so, only convenience.

-- 
John Cowan  cowan at ccil.org   http://ccil.org/~cowan
Promises become binding when there is a meeting of the minds and consideration
is exchanged. So it was at King's Bench in common law England; so it was
under the common law in the American colonies; so it was through more than
two centuries of jurisprudence in this country; and so it is today.
       --Specht v. Netscape

From seaman at noao.edu  Wed Jan  2 15:03:49 2008
From: seaman at noao.edu (Rob Seaman)
Date: Wed, 2 Jan 2008 13:03:49 -0700
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080102185850.GO14528@mercury.ccil.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<20080102030406.GJ14528@mercury.ccil.org>
	<3F4CF245-C067-43A3-A1C8-3B1308FC4646@noao.edu>
	<20080102185850.GO14528@mercury.ccil.org>
Message-ID: <931B3E26-E3F8-4D42-B90F-43A172AED88F@noao.edu>

John Cowan wrote:

> True but irrelevant,

You may not be alone in finding me irrelevant :-)

> since (with one exception) local civil time is not
> the subject of any international treaties that I know of.

But you were arguing a more absolute position:

> There is and can be no contract, and so non-repudiation remains  
> irrelevant.

You seem to find much irrelevancy in the world :-)

So now you admit there could be contracts in the form of treaties.  My  
job here is done.

>> but are somehow restricted by the ITU from issuing their own leap
>> seconds?
>
> They could, of course, do so, at the expense of being out of step  
> with the rest of the world.  It is choice, not compulsion, that  
> makes every nation synchronize its LCT with UTC either de jure or de  
> facto.

There is only choice in any arena.  Compulsion is another word for  
"remedy".  Obviously an entity with an army can attempt to do anything  
they want.  (I'll refrain from an irrelevant political statement  
here.)  The question is what happens economically, politically,  
scientifically, technically - etc. and so forth - as a result.

> Apart from the ALHP proponents, the desire of people who want to see  
> an end to leap seconds is to redefine the day as precisely 86400 SI  
> seconds, and when the discrepancy between MSolT
> (which is not quite LSolT, be it noted) and LCT becomes annoyingly  
> large in a particular place, to adjust the local UTC-TI offset  
> accordingly,

This notion results in a merry-go-round of timezones sliding around  
the planet - including the International Date Line.  I'm happy to  
accept your arguments about happy-go-lucky localities willy-nilly  
redefining their timezones, but as a result this seems a poor  
technical foundation for timekeeping in a world in which better  
timekeeping will be needed, not timekeeping at the whim of every local  
legislature and Presidente-for-life.

NOTE TO ITU LURKERS:  Consider here that partisans of quite diverse -  
opposing even - positions consider the Leap Hour Proposal to be Absurd  
(hence the ALHP).  Perhaps you could invest five minutes to consider  
what *will* actually happen as DUT1 grows?  It's all well and good to  
attempt to cheat on solar time, but even the current fractional second  
difference between a solar second and an SI second adds up and the  
difference is going to grow with time.  I won't belabor the arguments  
for why the ALHP is unacceptable, but John and I both think it is.   
How about developing some coherent and workable plan *before*  
dismantling the system we currently have?  Note that it isn't just a  
static offset, its the slope that matters.

> there is neither legal nor metaphysical necessity for it to be so,  
> only convenience.

The fact that we live on a spinning globe illuminated externally in a  
way that impacts a myriad facets of our civilization seems pretty  
"physical" to me :-)

This may not be convenient, but it remains a requirement we're  
beholden to.

Rob


From phk at phk.freebsd.dk  Wed Jan  2 15:08:00 2008
From: phk at phk.freebsd.dk (Poul-Henning Kamp)
Date: Wed, 02 Jan 2008 20:08:00 +0000
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: Your message of "Wed, 02 Jan 2008 13:03:49 MST."
	<931B3E26-E3F8-4D42-B90F-43A172AED88F@noao.edu> 
Message-ID: <1161.1199304480@critter.freebsd.dk>

In message <931B3E26-E3F8-4D42-B90F-43A172AED88F at noao.edu>, Rob Seaman writes:


>NOTE TO ITU LURKERS:  Consider here that partisans of quite diverse -  
>opposing even - positions consider the Leap Hour Proposal to be Absurd  
>(hence the ALHP).

The Leap Hour Proposal is not only absurd, it is also without relevance,
there is no historical reason to belive that our successors will
refrain from tampering with the timescales we lay down today many times
before a leap hour becomes imminent.

So lets forget the leap hour proposal, it's serves only the role
of a Post-It note with "fix it ?" written on it.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

From seaman at noao.edu  Wed Jan  2 16:21:27 2008
From: seaman at noao.edu (Rob Seaman)
Date: Wed, 2 Jan 2008 14:21:27 -0700
Subject: [LEAPSECS] Santa Claus in Kyrgyzstan
Message-ID: <0DBAE1A1-9628-4C0F-A896-27506063E4A4@noao.edu>

Here's an amusing discussion of GIS techniques applied to Santa's  
route selection:

	http://catless.ncl.ac.uk/Risks/24.93.html#subj7

Somehow this just seems pertinent to our discussion of the willy-nilly  
timezone algorithm applied to civil (or uncivil) timekeeping.  For  
instance, Santa is advised to fly from East to West such that  
Christmas Eve lasts two days (whatever a "day" means), not one.

Should the Right Jolly Old Elf sort his deliveries by UTC or local  
timezones?

Rob


From cowan at ccil.org  Wed Jan  2 16:34:11 2008
From: cowan at ccil.org (John Cowan)
Date: Wed, 2 Jan 2008 16:34:11 -0500
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <931B3E26-E3F8-4D42-B90F-43A172AED88F@noao.edu>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<20080102030406.GJ14528@mercury.ccil.org>
	<3F4CF245-C067-43A3-A1C8-3B1308FC4646@noao.edu>
	<20080102185850.GO14528@mercury.ccil.org>
	<931B3E26-E3F8-4D42-B90F-43A172AED88F@noao.edu>
Message-ID: <20080102213411.GQ14528@mercury.ccil.org>

Rob Seaman scripsit:

> So now you admit there could be contracts in the form of treaties.  My  
> job here is done.

Ah, good!  :-)

> There is only choice in any arena.  Compulsion is another word for  
> "remedy".  Obviously an entity with an army can attempt to do anything  
> they want.  

Right enough, but there is a fundamental difference between what
sovereign entities (like natural persons) have bound themselves
by agreement with their peers to do, and what they have not.
SI, for example, is the subject of a treaty that its signatories
are bound to respect; LCT is not.

> This notion results in a merry-go-round of timezones sliding around  
> the planet - 

The world's slowest merry-go-round, certainly; the best guess seems to be
that it will make a full turn in 28 ky, within the same order of magnitude
as the precession of the equinoxes.

Note that the Date Line is a whole different matter: it need not move
with the moving time zones.  Not so very long ago, the Philippines
were still on the New World side of it.

-- 
John Cowan      cowan at ccil.org        http://www.ccil.org/~cowan
        Is it not written, "That which is written, is written"?

From phk at phk.freebsd.dk  Wed Jan  2 16:40:56 2008
From: phk at phk.freebsd.dk (Poul-Henning Kamp)
Date: Wed, 02 Jan 2008 21:40:56 +0000
Subject: [LEAPSECS] Santa Claus in Kyrgyzstan
In-Reply-To: Your message of "Wed, 02 Jan 2008 14:21:27 MST."
	<0DBAE1A1-9628-4C0F-A896-27506063E4A4@noao.edu> 
Message-ID: <1590.1199310056@critter.freebsd.dk>

In message <0DBAE1A1-9628-4C0F-A896-27506063E4A4 at noao.edu>, Rob Seaman writes:
>Here's an amusing discussion of GIS techniques applied to Santa's  
>route selection:
>
>	http://catless.ncl.ac.uk/Risks/24.93.html#subj7
>
>Somehow this just seems pertinent to our discussion of the willy-nilly  
>timezone algorithm applied to civil (or uncivil) timekeeping.  For  
>instance, Santa is advised to fly from East to West such that  
>Christmas Eve lasts two days (whatever a "day" means), not one.
>
>Should the Right Jolly Old Elf sort his deliveries by UTC or local  
>timezones?

Well, given that he delivers at midnight, you have to admit that he
wouldn't benefit in any way from using your pet: solar time :-)

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

From dot at dotat.at  Wed Jan  2 17:07:57 2008
From: dot at dotat.at (Tony Finch)
Date: Wed, 2 Jan 2008 22:07:57 +0000
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <931B3E26-E3F8-4D42-B90F-43A172AED88F@noao.edu>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<20080102030406.GJ14528@mercury.ccil.org>
	<3F4CF245-C067-43A3-A1C8-3B1308FC4646@noao.edu>
	<20080102185850.GO14528@mercury.ccil.org>
	<931B3E26-E3F8-4D42-B90F-43A172AED88F@noao.edu>
Message-ID: <Pine.LNX.4.64.0801022206550.29627@hermes-1.csi.cam.ac.uk>

On Wed, 2 Jan 2008, Rob Seaman wrote:
>
> Perhaps you could invest five minutes to consider what *will* actually
> happen as DUT1 grows?

They should also worry about the error in the Gregorian calendar.

Tony.
-- 
f.a.n.finch  <dot at dotat.at>  http://dotat.at/
THAMES DOVER WIGHT PORTLAND PLYMOUTH BISCAY: EAST OR SOUTHEAST 5 TO 7.
MODERATE OR ROUGH. MAINLY FAIR, THEN OCCASIONAL RAIN OR SLEET. MODERATE OR
GOOD, OCCASIONALLY POOR.

From seaman at noao.edu  Wed Jan  2 18:29:35 2008
From: seaman at noao.edu (Rob Seaman)
Date: Wed, 2 Jan 2008 16:29:35 -0700
Subject: [LEAPSECS] Leapin' on the Merry-go-round
In-Reply-To: <20080102213411.GQ14528@mercury.ccil.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<20080102030406.GJ14528@mercury.ccil.org>
	<3F4CF245-C067-43A3-A1C8-3B1308FC4646@noao.edu>
	<20080102185850.GO14528@mercury.ccil.org>
	<931B3E26-E3F8-4D42-B90F-43A172AED88F@noao.edu>
	<20080102213411.GQ14528@mercury.ccil.org>
Message-ID: <1C0DE509-27FF-46BA-85B3-095B9A3B0D46@noao.edu>

Clearly 2008 is going to be another chatty year :-)

John Cowan wrote:

> The world's slowest merry-go-round, certainly; the best guess seems  
> to be
> that it will make a full turn in 28 ky, within the same order of  
> magnitude
> as the precession of the equinoxes.

Not sure where you got that.  Consider Steve Allen's Length of Day plot:

	http://www.ucolick.org/~sla/leapsecs/ancient.pdf

The leap deficit accumulates as the area under the curve.  If the  
curve is approximated as linear (appropriate over multi-million year  
periods of tidal slowing), then the area under the curve is  
quadratic.  Thus the "leap hour equivalents" accumulate more quickly  
further from the origin (which falls in the early 19th century).

The equation to integrate is something like:

	LOD = LOD(zero) + slope * centuries

But LOD(zero) can be identified as 86400 + delta(zero) since we  
already have accumulated a leap debt since the 19th century.  (The  
circa 1970 zero point had an offset from the actual smoothed  
LOD(1970).)  So:

	LOD = 86400 + delta(zero) + slope * centuries

But:

	DUT1 = integral (LOD - 86400) from 0 to N days

Rearranging and integrating both sides:

	DUT1 = integral (delta(zero) + slope * centuries) from 0 to N days

Delta(zero) is about 2 ms and slope is 1.7 ms/century (taking the  
middle trend line - should be steeper and thus more rapid accumulation  
over longer periods).  Changing variables, etc:

	DUT1 = 0.002 * N + 2.3e-8 * N^2

The accumulation of a leap deficit is thus roughly linear over the  
next couple of centuries, but becomes dominated by the quadratic term  
after that.  Obviously our poor calibration will fail at some point,  
but the *smoothed* effect has to be something like this unless the  
tidal transfer of angular momentum is much more creative than  
frictional braking.  The very long term (gigaday) LOD information  
seems consistent with something fairly linear in any event.

(The 600 year estimate for the first leap hour appears to have  
resulted from setting DUT1 = 1800s and solving for N = 657 years.   
Clearly if the ALHP were to be adopted, there would be a benefit in  
seesawing a half hour behind and then a half hour ahead, rather than a  
zero baseline sawtooth.)

This all adds up to a quadratically accelerating merry-go-round.   
Neglecting the linear term, we have the first full turn of the  
carousel completing in about 5,000 years.

As anybody with little kids knows, you only get a few turns of the  
carousel before they kick you off and load the next batch of kids -  
who would rather be on the Mad Hatter, anyway.  The second turn of the  
merry-go-round will take a bit over 2,000 years.  The third turn,  
significantly under 2,000 years with a leap hour equivalent every 60  
years.

(The one thing I'm sure of is that my math will be corrected if I've  
screwed it too badly :-)

Yes, the timelords can cheat mean solar time for a while, but the  
burden (dozens of leap hour equivalents) loom more and more  
frequently.  This differs from any calibration errors in the Gregorian  
calendar that maintain a decorous pace every few centuries or  
millennia.  (I can hear the suggestion now to fix it all with a  
February 29.5 whenever noon becomes midnight :-)

Better to deal forthrightly with the natural requirement for tweaking  
our clocks.

Rob


From phk at phk.freebsd.dk  Wed Jan  2 18:44:25 2008
From: phk at phk.freebsd.dk (Poul-Henning Kamp)
Date: Wed, 02 Jan 2008 23:44:25 +0000
Subject: [LEAPSECS] Leapin' on the Merry-go-round
In-Reply-To: Your message of "Wed, 02 Jan 2008 16:29:35 MST."
	<1C0DE509-27FF-46BA-85B3-095B9A3B0D46@noao.edu> 
Message-ID: <2140.1199317465@critter.freebsd.dk>

In message <1C0DE509-27FF-46BA-85B3-095B9A3B0D46 at noao.edu>, Rob Seaman writes:

>The accumulation of a leap deficit is thus roughly linear over the  
>next couple of centuries, [...]

Lets see, a couple of centuries ago the Napoleonic wars where in
full swing, I wonder how many of the rules and regulations laid
down back then we still follow to the word, without having refined,
reconsidered or replaced the with more modern approaches.

The metre convention from 1875 has barely ever managed to get the
ink to dry before somebody fiddles something in it.

Any rulemaking we may propose, that our grandchildren or later will
have to implement, is at best a pointless waste of time, they're going
to do it their own way anyway.

All we have to do is to leave them a clear notice what the issue
is, then they can decide if it is a problem and how they want to
fix it.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

From seaman at noao.edu  Wed Jan  2 21:25:26 2008
From: seaman at noao.edu (Rob Seaman)
Date: Wed, 2 Jan 2008 19:25:26 -0700
Subject: [LEAPSECS] Leapin' on the Merry-go-round
In-Reply-To: <2140.1199317465@critter.freebsd.dk>
References: <2140.1199317465@critter.freebsd.dk>
Message-ID: <0891D282-4876-4E43-91E4-7E511E1D5478@noao.edu>

Poul-Henning Kamp wrote:

> Lets see, a couple of centuries ago the Napoleonic wars where in  
> full swing,

And its our clocks and calendars that permit these to be placed in  
their proper place historically.  Tying these to the rotation of the  
Earth, rather than to some arbitrary ensemble of even interval clocks  
is...manifest destiny.

Dawn on September 7, 1812 obviously had more to do with the Battle of  
Borodino than some extension of an atomic clock that accelerates at  
1.7 ms/century relative to the natural rhythms pertaining to the battle.

I might also say that the first exercise from the graduate system  
engineering course I took last semester was an analysis of Borodino  
from the point of view of modern system engineering principles.  The  
past is with us still.

> I wonder how many of the rules and regulations laid down back then  
> we still follow to the word, without having refined, reconsidered or  
> replaced the with more modern approaches.

And your point is that the one standard that ties it all together from  
distant past to far future should drift aimlessly over the centuries?   
That the analysis of future battles should require knowledge of  
timezone usage precisely in those territories in which civil authority  
has collapsed?

Surely it is better to plan than to punt?

> Any rulemaking we may propose, that our grandchildren or later will  
> have to implement, is at best a pointless waste of time, they're  
> going to do it their own way anyway.

Again - you're making my point.  If your assertion is true, then it  
forever remains our responsibility to do the right thing right now,  
and to continue to evolve the standard under coherent design principles.

Time isn't just a frequency standard to tie computer networks together.

> All we have to do is to leave them a clear notice what the issue is,  
> then they can decide if it is a problem and how they want to fix it.


Ah yes - the Yucca Mountain Johnny gambit.

Rob


From sla at ucolick.org  Thu Jan  3 00:28:27 2008
From: sla at ucolick.org (Steve Allen)
Date: Wed, 2 Jan 2008 21:28:27 -0800
Subject: [LEAPSECS] Leapin' on the Merry-go-round
In-Reply-To: <2140.1199317465@critter.freebsd.dk>
References: <1C0DE509-27FF-46BA-85B3-095B9A3B0D46@noao.edu>
	<2140.1199317465@critter.freebsd.dk>
Message-ID: <20080103052827.GA1632@ucolick.org>

On Wed 2008-01-02T23:44:25 +0000, Poul-Henning Kamp hath writ:
> Any rulemaking we may propose, that our grandchildren or later will
> have to implement, is at best a pointless waste of time, they're going
> to do it their own way anyway.
>
> All we have to do is to leave them a clear notice what the issue
> is, then they can decide if it is a problem and how they want to
> fix it.

But if we are talking about international agreements, treaties,
or contracts, our grandparents have left us a very clear notice.

The International Meridian Conference of 1884 clearly indicated
that the Universal Day was to be a mean solar day, and by extension
the notion of Universal Time was mean solar.

In 1975 the 15th CGPM resolved that UTC, UT, and mean solar time
were approximately synonymous.

The countries who attended IMC or who are members of CGPM should
understand that to allow their ITU-R delegates to abandon leap seconds
in UTC is to violate both of these.

--
Steve Allen                 <sla at ucolick.org>                WGS-84 (GPS)
UCO/Lick Observatory        Natural Sciences II, Room 165    Lat  +36.99855
University of California    Voice: +1 831 459 3046           Lng -122.06015
Santa Cruz, CA 95064        http://www.ucolick.org/~sla/     Hgt +250 m

From magnus at rubidium.dyndns.org  Thu Jan  3 01:05:34 2008
From: magnus at rubidium.dyndns.org (Magnus Danielson)
Date: Thu, 03 Jan 2008 07:05:34 +0100 (CET)
Subject: [LEAPSECS] Leapin' on the Merry-go-round
In-Reply-To: <20080103052827.GA1632@ucolick.org>
References: <1C0DE509-27FF-46BA-85B3-095B9A3B0D46@noao.edu>
	<2140.1199317465@critter.freebsd.dk>
	<20080103052827.GA1632@ucolick.org>
Message-ID: <20080103.070534.-861052893.cfmd@bredband.net>

From: Steve Allen <sla at ucolick.org>
Subject: Re: [LEAPSECS] Leapin' on the Merry-go-round
Date: Wed, 2 Jan 2008 21:28:27 -0800
Message-ID: <20080103052827.GA1632 at ucolick.org>

Steve,

> On Wed 2008-01-02T23:44:25 +0000, Poul-Henning Kamp hath writ:
> > Any rulemaking we may propose, that our grandchildren or later will
> > have to implement, is at best a pointless waste of time, they're going
> > to do it their own way anyway.
> >
> > All we have to do is to leave them a clear notice what the issue
> > is, then they can decide if it is a problem and how they want to
> > fix it.
> 
> But if we are talking about international agreements, treaties,
> or contracts, our grandparents have left us a very clear notice.
> 
> The International Meridian Conference of 1884 clearly indicated
> that the Universal Day was to be a mean solar day, and by extension
> the notion of Universal Time was mean solar.
> 
> In 1975 the 15th CGPM resolved that UTC, UT, and mean solar time
> were approximately synonymous.
> 
> The countries who attended IMC or who are members of CGPM should
> understand that to allow their ITU-R delegates to abandon leap seconds
> in UTC is to violate both of these.

You could argue that ITU-R is working out of scope, if anything this is
increasingly more an ITU-T issue, if not handled properly within CGPM.
The issue lies within ITU-R for historical reasons, but if we are to modernize
timescales and put them in modern context, then the handling of the issue could
very well be the first place to start.

Cheers,
Magnus

From clive at demon.net  Thu Jan  3 01:31:53 2008
From: clive at demon.net (Clive D.W. Feather)
Date: Thu, 3 Jan 2008 06:31:53 +0000
Subject: [LEAPSECS] 2007-12-31 23:59:60 Z (sic)
In-Reply-To: <20080102185850.GO14528@mercury.ccil.org>
References: <Pine.LNX.4.64.0801012315510.7744@hermes-1.csi.cam.ac.uk>
	<20080101234704.GA22030@ucolick.org>
	<1199241447.7297.2.camel@glastonbury>
	<20080102025517.GA22736@ucolick.org>
	<20080102030406.GJ14528@mercury.ccil.org>
	<3F4CF245-C067-43A3-A1C8-3B1308FC4646@noao.edu>
	<20080102185850.GO14528@mercury.ccil.org>
Message-ID: <20080103063153.GA9699@finch-staff-1.thus.net>

John Cowan said:
> True but irrelevant, since (with one exception) local civil time is not
> the subject of any international treaties that I know of.
> 
> The EU insists that its members all change from standard to summer time
> at the same UTC second

Except that - as has been covered here before - the different translations
of the Directive (all with equal legal effect) use UTC, GMT, or are
ambiguous. So "same UTC second" isn't correct.

There's also a clearer case: the Treaty of Canterbury requires that local
time in the entire Concession area is the same as that used in France, even
for those parts of the Concession that are within the UK.

-- 
Clive D.W. Feather  | Work:  <clive at demon.net>   | Tel:    +44 20 8495 6138
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